This invention relates to a shake-out or knockout machine for use with a self-curing mold, and more particularly to a shake-out machine which is generally applicable to a shake-out operation for self-curing molds placed in various types and sizes of molding flasks.
This type shake-out machine consists of a body, a molding flask feeding means and a delivery means for delivering materials which have been dropped or knocked out from a molding flask.
Hitherto, an air cylinder machine or a hydraulic cylinder machine having a single plunger is used as a shake-out machine in a mass production line for a given size of molding flasks, irrespective of the types of molds, i.e., a green-sand mold having a relatively low retained-strength of sand and a self-curing mold having a relatively high retained-strength.
U.S. Pat. No. 2,525,572 which is a prior art for the present invention discloses a shake-out machine provided with two punch-out cylinders. This type shake-out machine however has to be subject to limitations arising from the size of a molding flask as well as from a limited number of plungers used (two in number) when used for self-curing molds having a high retained strength of sand. The machine has to be used exclusively for a specific size of molding flasks.